Dyslexia Not Linked to Lower IQ, Often Misunderstood

Actor Patrick Dempsey's revelation Wednesday night that he is dyslexic hasbrought new attention to the common misperception that the reading disability correlates with lesser intelligence.

In a TV interview with Barbara Walters, Dempsey, the star of the hit ABC show Grey's Anatomy, said he was diagnosed with dyslexia when he was 12 years old. Before that, he had been misdiagnosed and put in special education classes.

Dyslexia is a brain-based learning disability that specifically impairs a person’s ability to read. People with dyslexia typically read at levels significantly lower than expected, despite having normal intelligence, states the National Institute of Neurological Disorders and Stroke (NINDS), a branch of the National Institutes of Health.

Now 40, Dempsey told Walters that it’s “very hard” for him to read scripts, so he relies on memorization to master his character’s lines. Dempsey says he developed perseverance as a result of his experiences with dyslexia. “I have never given up,” he told Walters.

“Unfortunately, people assume that if you read poorly that correlates with having a low IQ,” Jeffrey Gruen, MD, says in an NINDS news release.

Gruen is an associate professor of pediatrics at Yale University’s medical school. With colleagues, he published a dyslexia study in the November 2005 edition of Proceedings of the National Academy of Sciences.

“This study confirms that dyslexic children can be typically smart and can have strong IQs. The reading disability is not a global effect on entire brain function,” Gruen says in the NINDS news release.

A positive view of dyslexia describes people with dyslexia as visual, multidimensional thinkers who are intuitive, highly creative, and excellent at hands-on learning. Many dyslexic people, like Dempsey, shine in the arts or creativity, design, computing, and lateral thinking.

When his study was published, Gruen told WebMD that people with dyslexia are "intelligent, smart, and talented," and that dyslexia is "no fault of their own.” People with dyslexia “learn to read differently, and we just need to accommodate them.”

Gruen’s study found a gap in the DCDC2 gene in many dyslexic patients. That finding suggests that genes play an important role in dyslexia, Gruen says.

More research lies ahead to learn more about that gene gap. For instance, it’s not certain if everyone with that gap will develop dyslexia. Some dyslexia patients in Gruen’s study didn’t have the gene gap.

Dyslexia varies from person to person. The International Dyslexia Association (IDA) states that some people with dyslexia -- but not all -- read and write letters in the wrong order.

According to the IDA, some people with dyslexia have issues with learning to speak, organizing written and spoken language, learning letters and their sounds, memorizing number facts, spelling, reading, learning a foreign language, and doing math correctly.

Not everyone with those problems has dyslexia. Formal testing is needed for a diagnosis, states the IDA.

Treatment and Prognosis

According to the NINDS, dyslexia treatment should mainly focus on the specific learning problems of affected individuals. The usual course is to modify teaching methods and the educational environment to meet the specific needs of the individual with dyslexia.

Spotting dyslexia early can help, the NINDS notes.

“The disability affects such a wide range of people, producing different symptoms and varying degrees of severity, that predictions are hard to make,” states the NINDS’ web site.

“The prognosis is generally good, however, for individuals whose dyslexia is identified early, who have supportive family and friends and a strong self-image, and who are involved in a proper remediation program,” the NINDS says.